1. Field of the Invention
The present invention relates to a circuit-interrupting device and more particularly to a high-voltage circuit-interrupting device which utilizes a moving contact, a source of pressurized-dielectric gas, and a stored energy source for moving the movable contact.
2. Brief Description of the Prior Art
Various types of circuit-interrupting devices are well known. One species of circuit-interrupting devices includes fuses or fuse-like devices, subspecies of which are those circuit-interrupting devices disclosed in the following commonly assigned, U.S. Patent Applications, all filed May 24, 1978: Ser. No. 909,144 and Ser. No. 909,145, now U.S. Pat. No. 4,183,005, in the names of O. Meister and T. J. Tobin; and Ser. No. 909,146, now U.S. Pat. No. 4,161,711, in the name of O. Meister. All three of these patent applications are specifically incorporated by reference hereinto.
The above-noted subspecies includes circuit-interrupting devices of two different types. The first type includes an arcing rod which is movable away from a stationary contact following the fusing of a fusible element due to an overcurrent through the device. A pressurized dielectric fluid is directed from the port of a container at an elongating arc which is formed between the moving arcing rod and the contact. A diaphragm, normally contacted by the arcing rod, normally closes the port and prevents a stored energy device, such as a spring, from moving the arcing rod. The diaphragm itself is also fusible. The fusible element is connected to the arcing rod in such a manner that it normally shunts the majority of current through the device away from the fusible diaphragm. Upon the occurrence of an overcurrent through the device, the fusible element fuses or melts which causes all current to now flow through the fusible diaphragm. Ultimately, the fusible diaphragm melts or fuses, releasing the arcing rod to the action of the spring and opening the port to permit the dielectric fluid to be directed at the elongating arc formed between the arcing rod and the stationary contact.
The second type of interrupting device within the subspecies disclosed in the above-noted patent applications includes a movable contact or arcing rod which is moved away from a stationary contact following an overcurrent through the device. Arcing rod movement is initiated by the action of an ignitable power cartridge on a piston-cylinder arrangement connected to the arcing rod. A quantity of pressurized dielectric fluid in a container is normally prevented from escaping through a port thereof by a rupturable or tearable diaphragm closing the port. Movement of the arcing rod by the power cartridge causes the arcing rod, which is connected to the diaphragm, to tear or rupture the diaphragm, thus forming an opening therein permitting the fluid to escape and to be directed at the elongating arc struck between the moving arcing rod and the contact.
In both types of devices it has been found prudent to ensure that the opening formed in the diaphragm has an appropriate shape and a sufficiently large size to ensure that the dielectric fluid escapes from the port in sufficient quantity and at a sufficient velocity to extinguish the arc.
Thus, the present invention comprises an improvement of the devices disclosed and claimed in the above-noted patent applications.